Thanks. I have a followup question. When my train room was built, I had the electrician run a separate ground wire from the actual earth ground. I also have a circuit for all the wall receptacles which goes around the room but at a level below the tracks. Finally, I have a 20 AMP isolated circuit that resides in the middle of the room that I am using to power the layout with 12 bricks and a ZW-L. For my ground wire, can I run it off the separate earth ground or should I connect it to either the circuit that goes around the room or the circuit that is powering the layout.
Thoughts and comments are appreciated.
GREG in Wisconsin.